This takes a little effort, but the wonderful combination of sweet caramelized onions, the saltiness of the pancetta and the rich flavor of the cheese is so appealing. I've included tips for caramelizing onions.
Use 1-2 pastry sheets as required to fit the tart pan
For the reduced butter easy pie crust:
The custard filling:
◆Whole egg (size M)
◆Salt and pepper
a small amount
◆Nutmeg, cayenne pepper
a small amount
The additional fillings:
Gruyère cheese (see Step 15)
80 g to 100 g
Pancetta (or a block of bacon if you don't have pancetta)
Mushrooms (I used bunapi-shimeji mushrooms this time)
Olive oil, black pepper, parsley if you have i
Preliminaries. Cook the caramelized onions. See Steps 16 onwards. Cut the butter into 1cm dice and chill it well. If you are using a frozen puff pastry, take it out of the freezer.
Sift the flour, salt and sugar together. (Skip this part if you're using frozen puff pastry.)
Put the Step 2 mix and chilled butter in a bowl and use a pastry cutter to cut the butter into the flour. Add cold water and form into a ball of dough.
If you use a food processor for Step 3 it's very easy. (Freeze the diced butter.)
Put the Step 3 dough on a work surface and roll it out with a rolling pin. Cut in half, layer the halves, and roll out. Repeat this 3 times. (It's the same as when you are making scones.)
Roll out the dough so that it's a bit bigger than the tart pan. (If you are using frozen puff pastry, roll it out to fit the pan in the same way.)
Put the dough on the tart pan, and press it into the corners of the pan carefully so that there are no gaps. Cut off the excess dough.
Pierce the bottom of the crust with a fork.
Line the crust with a piece of parchment paper, and put in some pie weights. Bake for 20 minutes in a 200°C oven. Remove the pie weights and bake for another 3 minutes.
I don't brush the crust with egg yolk and bake it again (this is often done to strengthen the crust). Since the crust will be lined on the bottom with the caramelized onions, there's no need to do this in this case.
While the crust is baking, cut the stem ends off the shimeji mushrooms and shred them. Cut the pancetta into thin strips. Sauté both in a small amount of oil. (Add black pepper to taste.)
When the tart crust is baked, line the bottom evenly with the caramelized onions. Add the Step 11 sauté and finely chopped up cheese evenly.
Mix the ◆ ingredients together and pour it into the tart. The amount of ◆ I've listed will fill the tart up to the brim. Be careful that it doesn't spill out when you move the tart into the oven.
Preheat the oven to 180°C, then lower the temperature to 160°C. Bake for 40 minutes. (I topped it with some shredded Italian parsley.) When the tart has cooled down a bit, take it out of the pan.
Sprinkle with cayenne pepper and parsley to taste. You can use any other delicious melting cheese instead of the Gruyère cheese. You can also mix several types of cheese.
To make the caramelized onions: Put water in a cup or bowl, and have a teaspoon ready. Slice the onion thinly with the grain as shown.
Put the sliced onion in a sturdy plastic bag or a heatproof container, and microwave at 600w for 5 minutes. Drain into a sieve (it's hot so be careful not to burn yourself).
Put the oil in a frying pan and sauté the onions. Add a little salt, and start cooking over high heat to evaporate the moisture quickly. When the moisture is gone, lower the heat.
Keep sautéing while making sure not to let it burn. If the bottom of the frying pan starts to brown, add 2 teaspoons of the water that you prepared in Step 16 on the browned part.
Mix the water with the onion, and continue sautéing. Keep adding water and sautéing repeatedly, about 5 to 6 times, until the onions have caramelized.
The brown bits on the frying pan is the sugar that comes out of the onion. By mixing this back in to the onions, they will become beautifully browned and caramelized.
Warning: If they get black and burned, they will be too bitter to use. It does take effort, but please cook the onions with care. With this method, I reduced the usual cooking time of 50 minutes to 25 minutes.
I pre-cooked the onion in the microwave, but another way to cut down on the cooking time is to slice the onions, put them in a single layer and freeze them to bread down the fibers before sautéing them.
There are several ways of cutting down the cooking time I think, but do sauté the onions with care. If you sauté them as in Step 21, they will become really sweet and delicious. They will decrease to 1/5 the volume.
The amount of liquid filling needed with varies depending on how much you sauté the onions. Please adjust accordingly. Adjust the amount of cheese to taste too - use between 80 to 100 g.
Story Behind this Recipe
I make quiche with various fillings, but my favorite is caramelized onions. This is my own variation of a recipe I learned a long time ago. It takes some time to make caramelized onions, but your hard work is sure to be rewarded by praise. We serve this quiche to guests.
Usually, the dough is rested in Step 5, but this dough is easy to handle so you can just go ahead and roll it out. (If the dough gets too soft to handle when the weather is hot, refrigerate it for a while.) It takes a lot of time and effort to make the caramelized onions, so if you make it the day before and refrigerate it, it's a lot easier to make the quiche. You can freeze it too. Add salt sparingly.